title: Molecular pathogenesis of juvenile nasopharyngeal angiofibroma in brazilian patients.
abstract: Juvenile nasopharyngeal angiofibroma (JNA) is a vascular tumor of the nasopharynx that accounts for 0.5% of all cancers of the head and neck. It primarily affects males aged 14-25 years. Of the many genes that mediate the development of JNA, GSTM1 has been most frequently associated with this vascular tumor. The loss of expression of GSTM1 (null genotype) is linked to the development of these tumors. The aim of this cross-sectional case study was to examine the prevalence of the GSTM1-null genotype in Brazilian patients with JNA. DNA was extracted from the leukocytes of blood samples from 10 patients. GSTM1 genotypes were analyzed using a PCR-based assay that was designed to identify the wild-type allele of GSTM1. All 10 patients (100%) were males, with a mean age of 17.8 years. The null genotype for GSTM1 was noted in 4 patients (40%)-1 (10%) at Fisch stage I, 1 (10%) at stage III, and 2 (20%) at stage II. No patient with this genotype had stage IV disease. There was no correlation between Fisch classification and GSTM1 genotype (P = .5695). The correlation between age at diagnosis and GSTM1 genotype was not significant (P = .728). The present findings indicate that there is evidence of an association between the GSTM1-null genotype and JNA in this studied Brazilian population.
authors.affiliation: 1Department of Otorhinolaryngology and Head-Neck Surgery of the Faculty of Medicine of São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, São Paulo, Brazil.
authors.forename: Maurício Pereira
authors.initials: MP
authors.lastname: Maniglia
authors.forename: Maria Estela Bellini
authors.initials: ME
authors.lastname: Ribeiro
authors.forename: Nauyla Miranda da
authors.initials: NM
authors.lastname: Costa
authors.forename: Marta Lúcia Gabriel
authors.initials: ML
authors.lastname: Jacomini
authors.forename: Thiago Bittencourt Ottoni de
authors.initials: TB
authors.lastname: Carvalho
authors.forename: Fernando Drimel
authors.initials: FD
authors.lastname: Molina
authors.forename: Vânia Belintani
authors.initials: VB
authors.lastname: Piatto
authors.forename: José Victor
authors.initials: JV
authors.lastname: Maniglia
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D018322:Angiofibroma / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D008297:Male; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D009367:Neoplasm Staging
chemical_list: D005982:Glutathione Transferase